Carbon impurities on graphene synthesized by chemical vapor deposition on platinum

Journal Article · Mon Jul 28 00:00:00 EDT 2014 · Journal of Applied Physics

DOI:https://doi.org/10.1063/1.4891200· OSTI ID:22308551

Ping, Jinglei

We report nanocrystalline carbon impurities coexisting with graphene synthesized via chemical vapor deposition on platinum. For certain growth conditions, we observe micron-size island-like impurity layers which can be mistaken for second graphene layers in optical microscopy or scanning electron microscopy. The island orientation depends on the crystalline orientation of the Pt, as shown by electron backscatter diffraction, indicating growth of carbon at the platinum surface below graphene. Dark-field transmission electron microscopy indicates that in addition to uniform single-crystal graphene, our sample is decorated with nanocrystalline carbon impurities with a spatially inhomogeneous distribution. The impurity concentration can be reduced significantly by lowering the growth temperature. Raman spectra show a large D peak, however, electrical characterization shows high mobility (∼8000 cm{sup 2}/Vs), indicating a limitation for Raman spectroscopy in characterizing the electronic quality of graphene.

• OSTI ID: 22308551
• Journal Information: Journal of Applied Physics, Vol. 116, Issue 4; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA); ISSN 0021-8979
• Country of Publication: United States
• Language: English

Related Subjects

75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
CARBON
CARRIER MOBILITY
CHEMICAL VAPOR DEPOSITION
DIFFRACTION
DISTRIBUTION
GRAPHENE
IMPURITIES
LAYERS
MONOCRYSTALS
NANOSTRUCTURES
OPTICAL MICROSCOPY
PLATINUM
RAMAN SPECTRA
RAMAN SPECTROSCOPY
SCANNING ELECTRON MICROSCOPY
SURFACES
TRANSMISSION ELECTRON MICROSCOPY